Delivery system for topical skin care agents

ABSTRACT

This invention relates to a delivery system which comprises a topical skin care agent, a top layer and a bottom layer where at least one of said top layer and said bottom layer comprises an apertured film having protuberances therein, where said top layer and said bottom layer are attached to eachother leaving a pouch between said top layer and said bottom layer, where said protuberances of said apertured film face said pouch, and where said pouch contains said topical skin care agent.

BACKROUND

[0001] The skin is said to be the largest organ in the human body. Likeother organs of the body, the skin needs care to maintain it in optimalcondition and treatment to cure it when it exhibits the symptoms ofdisease. Often the skin is maintained using skin care products, such ashumectants, emollients, and vitamins; and is treated using medicinalagents. Although some agents used to treat the skin are administeredorally, many agents are administered topically, and are generally knownas topical skin care agents.

[0002] When administering topical skin care agents one of the mainconcerns is the ease of application to such a large organ. One commonmethod of administering such agents to this large surface area consistsof bathing the individual in a water bath, which contains the topicalskin care agent. Although this method permits easy access to large areasof an individual's skin, it is not without problems. One problem iscaused by the fact that many topical skin care agents are not easilydispersed in the bath water. Many of these agents just clump in the bathwater and settle to the bottom of the tub. Unfortunately this clumpingand settling is unattractive to the user and often the clumping andsettling reduces the effect of the topical agent. One such topicalagents which is prone to clumping and settling when administered by bathwater is oatmeal.

[0003] Oatmeal is known to soothe the itching sensation of the skin,which is associated with the common childhood disease, Chicken Pox.Typically a person who is afflicted with Chicken Pox has red itchy andpainful “pox type” lesions covering their body. When an infectedindividual is bathed in a bath containing oatmeal, the itchingassociated with the lesions is alleviated. Unfortunately, oatmeal is noteasily dispersed in water. Powdered bath formulations containing oatmealare typically formulated with other materials to aid the dispersion ofoatmeal into water. Often these powdered formulations may only be addedto the bath by sprinkling small portions of the powder under a faucet ofrunning water. Even with this method of adding the powdered formulation,the oatmeal often clumps and settles to the bottom of the bathtub andresults in an inferior and incomplete treatment.

[0004] An alternate means of adding oatmeal to a bath is the use of anoatmeal bath tablet. Oatmeal bath tablets generally deliverssignificantly less oatmeal than the process described above.

[0005] Therefore, there is a need for a delivery system that providesless mess and more convenience than the current delivery systems fortopical medicinal and skin care products. Additionally, because thetopical medicinal and skin care products may be solids having smallparticle sizes, the delivery system should be designed to retain smallparticle size solids when in the dry state.

[0006] Others have attempted to produce delivery systems for applyingcolloidal oatmeal to a person's skin. For example, U.S. Pat. No.5,219,340 discloses an applicator for applying a colloidal oatmealtreatment product to a person's skin. The applicator is formed from aporous material including cotton and cotton/polyester blends.

[0007] Despite these efforts, there is a continuing need for a deliverysystem that provides less mess and more convenience than the currentdelivery systems for topical skin care agents.

SUMMARY OF THE INVENTION

[0008] This invention relates to a delivery system for topical skin careagents. This delivery system comprises a topical skin care agent, a toplayer and a bottom layer where at least one of said top layer and saidbottom layer comprises an apertured film having protuberances therein,where said top layer and said bottom layer are attached to eachotherleaving a pouch between said top layer and said bottom layer, where saidprotuberances of said apertured film face said pouch, and where saidpouch contains said topical skin care agent.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009]FIG. 1 is a perspective view of a delivery system of theinvention.

[0010]FIG. 2 illustrates the rough side of an apertured film

[0011]FIG. 3 illustrates the smooth side of an apertured film

[0012]FIG. 4 illustrates a cross sectional view of FIG. 1 along line a

[0013]FIG. 5 illustrates a cross section view of FIG. 1 along line awhich includes the topical skin care agent.

DETAILED DESCRIPTION OF THE INVENTION

[0014] This invention relates to a a delivery system comprising atopical skin care agent, a top layer and a bottom layer where at leastone of said top layer and said bottom layer comprises an apertured filmhaving protuberances therein, where said top layer and said bottom layerare attached to eachother leaving a pouch between said top layer andsaid bottom layer, where said protuberances of said apertured film facesaid pouch, and where said pouch contains said topical skin care agent.

[0015] The delivery systems of this invention are sachet type poucheswhich are designed to hold topical skin care agents internally intactwithout leakage of said agents. A perspective view of an exemplarydelivery system is illustrated in FIG. 1. The top layer, 1, and thebottom layer, 2, of the delivery system are attached to one another bymeans known in the art. Typically the top layer and the bottom layer areattached by fusing them with heat. Alternatively, these layers may besewn together or glued with an adhesive. Any method of attachment whichallows for the forming of a pouch, 3, which is used to contain a topicalskin care agent may be used so long as the method of attachment does notfuse the pouch portion of the delivery system or damage the topical skincare agent.

[0016] At least one layer of the delivery systems of the invention ismade of an apertured film. Apertured films are textured films whichcontain raised protuberances which may be made by a number of methods.Generally speaking, apertured films possess a “rough” side, whichcontains the raised protuberances as shown in the micrograph of theapertured film in FIG. 2, and an opposing “smooth” side as shown in themicrograph of the apertured film in FIG. 3. By “smooth” side, it ismeant the side from which the raised protuberances originate. Theprotuberances in such apertured films are generally cone-shaped. Thesefilms may be made from any polymeric material including, but not limitedto polyethylene, metallocene catalyzed polyethylene, polypropylene, andcopolymers thereof, and ethylene vinyl acetate copolymers. Suchapertured films are disclosed in U.S. Pat. Nos. 3,054,148, 3,394,211,3,929,135, 4,324,246, 4,342,314, 4,463,045, 4,741,877, and 5,006,394,each of which is hereby incorporated by reference.

[0017] The size of the apertures and the number of apertures per squarecentimeter may vary, depending on the particle size distribution of thetopical skin care agent which is being delivered. Generally, if thetopical skin care agent is colloidal oatmeal, the size of the aperturesin the film may range from 25 microns to 100 microns, preferably from 50microns to 75 microns. The number of apertures per square centimeter offilm may range from 10 to 75, preferably from 15 to 40, more preferablyfrom 20 to 30. The apertured films may contain Microban™ or othersuitable anti-bacterial agents in effective amounts. Examples ofsuitable commercial apertured films include those available fromTredegar Film Products, Inc. under the tradename, “VisPore®,” fromPolymer Group, Inc. under the tradename, “Reticulon®, or from Guial Inc.under the tradename, “Zeole” with the “VisPore®” film being preferred.

[0018] In the delivery systems of the invention, the rough side of thefilm faces the pouch portion of the delivery system, as illustrated inFIG. 4. FIG. 4 illustrates a cross section view along line a of FIG. 1.The top layer, 1, and the bottom layer, 2 of the device illustrated inthis figure comprise an aperatured film. The rough side of theaperatured films face the pouch, 3, of the device. The topical skin careagent is not illustrated in FIG. 4 in order to more clearly illustratethe top layer and the bottom layer of this device. FIG. 5 illustrates across sectional view along line a of FIG. 1, where the topical skin careagent, 4, is illustrated within pouch, 3, of the device.

[0019] Both the top layer and the bottom layer of the delivery system ofthe invention may comprise apertured films, however, if only one layeris an apertured film, the other layer may be made from any porousmaterials. Other suitable materials of construction for the top layerand the bottom layer include, but are not limited to natural fiber andsynthetic fiber nonwoven materials, polyethylene films, andpolypropylene films. The nonwoven materials may be hydrophobic orhydrophilic. An example of a natural fiber hydrophobic nonwoven materialis cotton. Examples of synthetic fiber hydrophobic nonwoven materialsinclude, but are not limited to, rayon and polypropylene. The nonwovenmaterial may contain more than one component and may be prepared byvarious processes known in the art. Bicomponent spunbond nonwovenmaterials, which make a web like pattern are preferred. Suitablenonwovens are commercially available, for example through PGI Nonwovens.Examples of such nonwovens include, but are not limited to PGI 6757, PGI67DCO, and PGI 6705.

[0020] In addition, the top layer and the bottom layer may comprise anumber of the fabrics. For example the top layer may comprises anapertured film and a second fabric which is selected from natural fiberand synthetic fiber hydrophobic nonwoven materials as described above.The second fabric may be laminated to the apertured film. Alternatively,the second fabric may be sewed or layed over the apertured fabric. Thesecond fabric may be placed on either the rough face or the smooth faceof the apertured film. However, the preferred location of the secondfabric is on the smooth face of the film.

[0021] As used herein, the term “topical skin care agent”, refers tomedicinal and cosmetic agents, which are dispersable in water, and whichare used to topically treat the skin. Typical cosmetic agents includebut are not limited to humectants, emollients, and vitamins. Typicalmedicinal agents include but are not limited to oatmeal, bicarbonate ofsoda, colloidal oatmeal, oilated colloidal bath treatment, surfactantbased colloidal oatmeal cleanser, other cleanser systems, soy powder,herbal medicines and combinations thereof. Although these agents areavailable in solid and liquid formulations, the preferred formulation ofsaid topical skin care agents is a solid formulation.

[0022] Further, topical skin care agents may include herbal medicinesand combinations thereof may be included in the invention. The herbalmedicine may treat more than one condition. Suitable herbal medicinesinclude, but are not limited to, antifungal agents such as CentaureaCyanus, Kalmia Latifolia and the like; antihistamine agents such asMandragora Vernalis, Tanacetum Parthenium and the like; anti-infectiveagents such as Acacia Catechu, Aloe Barbadensis, Convallaria Majalis,Echinacea, Eucalyptus, Mentha Piperita, Rosa Canina, Sassafras Albidum,and the like; anti-inflammatory agents such as Fragaria Vesca,Matricaria Chamomilla, Salvia Officinalis and the like; antipruriticagents such as Anagallis Arvensis, Oenothera Biennis, VerbenaOfficinalis and the like; skin and mucous membrane agents such asAesculus Hippocastanum, Avena Sativa, Baptista Tinctoria, DigitalisPurpurea, Hamamelis Virginiana, Helianthus Annuus, Hypericum Perforatum,Lawsonia Inermis, Nerium Odoratum and the like; and wound care agentssuch as Calendula Officinalis, Cinnamomum Verum, Coffea Arabica, ColaAcuminata, Solidago Species and the like. The preferred topical skincare agent is colloidal oatmeal.

[0023] As used herein, colloidal oatmeal means the powder resulting fromthe grinding and further processing of whole oat grain meeting UnitedStates Standards for Number 1 or Number 2 oats. The colloidal oatmealhas a particle size distribution as follows: not more than 3 percent ofthe total particles exceed 150 micrometers in size and not more than 20percent of the total particles exceed 75 micrometers in size. Examplesof suitable colloidal oatmeals include, but are not limited to, BeaconColloidal oatmeal and Promix Colloidal Oatmeal.

[0024] The amount of topical skin care agent which is contained in thedelivery systems of the invention, varies depending upon the type ofagent used. Typically, the delivery systems of the invention containfrom about 1 gram to about 100 grams of the topical skin care agent.Preferably the delivery systems contain from about 10 grams to about 50grams, more preferably from about 15 grams to about 45 grams of thetopical skin care agent.

[0025] Although the topical skin care agent of the invention may beplaced directly in the pouch of the delivery system, these agents may beinitially contained within a water soluble film which includes but isnot limited to, polyvinyl alcohol polyvinyl acetate, and cellulose. Thiscontained topical skin care agent may be in turn directly inserted intothe pouch of the delivery system of the invention.

[0026] Typically, the delivery systems of the invention are exposed tobath water by funneling the water through the sachet while the bath isbeing drawn. This method results in the complete dispersion, dissolutionand delivery of the topical skin care products contained within thepouch of the delivery system.

[0027] In one embodiment of the present invention, the top layer and thebottom layer are apertured films. In a second embodiment of the presentinvention, one layer is an apertured film and the other layer is anatural fiber or synthetic fiber hydrophobic nonwoven material. In yet athird embodiment of the invention, topical skin care agent is containedin a water-soluble film.

[0028] The delivery systems of the invention may be made in any shape,where those shapes which include but are not limited to, round, oval,rectangular, square, and triangular devices. The size of the article ofthe invention may be adapted to accommodate the amount of topicalmedicinal and skin care products to be delivered. Generally, a squarearticle of the invention may range in size from 5 cm×5 cm to 15 cm×15cm, preferably from 7.5 cm×7.5 cm to 12.5 cm×12.5 cm. A circular articleof the invention may range in outer diameter from 5 cm to 20 cm,preferably from 7.5 cm to 17.5 cm, more preferably from 10 cm to 15 cm.

[0029] The following examples are intended to demonstrate possibledelivery system of the invention. The examples should not be construedas limiting the scope of the invention.

EXAMPLE 1 Preparation of Pouches Utilizing Apertured Films

[0030] For Sample A, an 11 cm×11 cm square pouch was prepared utilizingTredegar Vispore film lot 25181 (a nonwoven/apertured film laminate) asthe top and bottom layer. The apertured films were oriented so that theprotuberances (rough side) faced the inside of the pouch. The aperturedfilms were attached to each other on 3 sides by heat sealing. The pouchwas filled with 21 grams of Beacon colloidal oatmeal. The pouch was thenheat sealed on the 4^(th) side. For Sample B, the process of Sample Awas repeated except Tredegar Vispore film lot 25178 (anonwoven/apertured film laminate) was substituted for lot 25181.

[0031] For Sample C, the process of Sample A was repeated except Promixcolloidal oatmeal was substituted for Beacon colloidal oatmeal. ForSample D, the process of Sample A was repeated except Promix oatmealwith a particle size of 75 micrometers was substituted for Beaconcolloidal oatmeal. Sample E was Promix colloidal oatmeal without apouch. Sample F was Beacon colloidal oatmeal without a pouch. Samples D,E, and F were comparative Samples.

EXAMPLE 2 Reversed Orientation of Protuberances

[0032] Sample G was a pouch prepared as in Sample A above, except theprotuberances were oriented towards the outside of the article.

EXAMPLE 3 Effect of Film on Dispersion

[0033] The effect of the number of apertures per square centimeter offilm on dispersion of colloidal oatmeal was tested. Samples wereprepared as in Sample A above, except the Tredegar film was varied toprovide different numbers of apertures per square centimeter of film.Sample H contained 40 apertures per square centimeter. Sample Icontained 22 apertures per square centimeter.

EXAMPLE 4 Dispersion Testing

[0034] The pouches prepared in Examples 1, 2, 3, and 4 were tested fordispersion of the colloidal oatmeal in water. The test was performed ina sink. A pouch was placed in the empty sink under a faucet with thewater running at full force over the pouch. The water temperature wasfrom 35° C. to 40° C. The pouch was agitated under the water, and thetime for the colloidal oatmeal to dissolve and disperse from the pouchwas measured. Samples were considered to fail if the colloidal oatmealdid not completely disperse without squeezing the pouch within 3minutes. The results are reported in Table 1. TABLE 1 Sample Result APass - Completely dispersed within two minutes. B Pass - Completelydispersed within one and one half minutes. C Pass - Completely dispersedwithin two and one half minutes. D Failed - After 3 minutes, 50% oatmealremained in pouch. E Failed - 75% dispersed, large particles floating,some settling. F Failed - 75% dispersed, slight clumping, some settling.G Failed - required manual extrusion to release oatmeal. H Pass -Completely dispersed within one and one half minutes. I Pass -Completely dispersed within one minute.

[0035] The data above demonstrates that the delivery system of thepresent invention provides less mess and more convenience than thecurrent delivery systems for topical medicinal and skin care products.The number of apertures per square centimeter affects the dispersionrate of the topical skincare agents products, but the films tested bothpassed the test for dispersion.

We claim:
 1. A delivery system comprising a topical skin care agent, atop layer, and a bottom layer where at least one of said top layer andsaid bottom layer comprises an apertured film having protuberancestherein, where said top layer and said bottom layer are attached toeachother leaving a pouch between said top layer and said bottom layer,where said protuberances of said apertured film face said pouch, andwhere said pouch contains said topical skin care agent.
 2. The deliverysystem of claim 1, wherein the topical skin care agent is selected fromone or more members of the group consisting of oatmeal, colloidaloatmeal, oilated colloidal bath treatment, surfactant based colloidaloatmeal cleanser, cleanser systems, and soy powder.
 3. The deliverysystem of claim 1 wherein said top layer and said bottom layer comprisean apertured film.
 4. The delivery system of claim 1 wherein said toplayer and said bottom layer comprise an apertured film which islaminated to a natural fiber or a synthetic fiber hydrophobic nonwovenmaterial.
 5. The delivery system of claim 4 wherein the hydrophobicnonwoven material is a bicomponent spunbound nonwoven.
 6. The deliverysystem of claim 5 wherein the bicomponent spunbound nonwoven material isselected from the group consisting of PGI 6757, PGI 67DCO, and PGI 6705.7. The delivery system of claim 1 wherein the apertures of either saidtop layer or said bottom layer have a size ranging from about 25 micronsto about 100 microns.
 8. The delivery system of claim 1 wherein theapertures of either said top layer or said bottom layer have a sizeranging from about 50 microns to about 75 microns.
 9. The deliverysystem of claim 1 wherein the number of apertures per square centimeterof film of either said top layer or said bottom ranges from about 10 toabout 50 apertures.
 10. The delivery system of claim 1 wherein thenumber of apertures per square centimeter of film of either said toplayer or said bottom layer ranges from about 15 to about 40 apertures.11. The delivery system of claim 1 wherein either said top layer or saidbottom layer is selected from the group consisting of natural fiber andsynthetic fiber hydrophobic nonwoven materials.
 12. The delivery systemof claim 1 wherein, said topical skin care agent is contained in awater-soluble film.
 13. The delivery system of claim 12 wherein, saidwater-soluble film is selected from the group consisting of polyvinylalcohol, polyvinyl acetate, and cellulose derivatives.
 14. The deliverysystem of claim 12 wherein, said top layer and said bottom layercomprise an apertured film having a bicomponent spunbond nonwovenmaterial laminated to said apertured film and said topical skin careagent is collodial oatmeal.